Noah's request seemed to go beyond what the black dragon was willing to accept. His power was undeniable, but he remained a mere rank 8 existence. He couldn't request for the most ancient creature in the entire world to be his teacher.
Even the gentle silver dragon appeared annoyed by that request. She couldn't comprehend how Noah could even think about asking that. He was a single law while the green creature literally had the fate of the world on its shoulders.
However, the green dragon didn't immediately refuse Noah's request. Its eyes sharpened as it tried to inspect his existence and uncover his true nature.
The green dragon had lived long enough to develop unique instincts that made it understand when something could help against Heaven and Earth, and those feelings rang when it inspected Noah. Also, it felt hard to evaluate his overall power. Noah wasn't trying to shield himself from the inspection, but the leader still struggled to get a clear view of his existence.